Questions and Answers
What type of skin lesion is characterized by a well-circumscribed elevation of the epidermis filled with clear fluid and measures less than 1 cm in diameter?
Abscesses are large, fluid-filled elevations of the epidermis that are greater than 1 cm in diameter.
False
What is the term for a small, pus-filled elevation of the epidermis?
Pustule
A __________ is a larger vesicle, greater than 1 cm in diameter, that often appears as a blister.
Signup and view all the answers
Match the following primary skin lesions with their definitions:
Signup and view all the answers
Which primary lesion typically represents a benign heritable condition of hyperpigmentation?
Signup and view all the answers
Secondary lesions evolve directly from primary lesions and are more important diagnostically.
Signup and view all the answers
What type of skin lesion might indicate an allergic reaction in animals?
Signup and view all the answers
What is a comedo?
Signup and view all the answers
Alopecia refers to an increased amount of hair.
Signup and view all the answers
What is hypertrichosis?
Signup and view all the answers
Leukoderma is characterized by __________ of skin.
Signup and view all the answers
Match the following skin conditions with their descriptions:
Signup and view all the answers
Which of the following factors does NOT affect melanin pigment production?
Signup and view all the answers
Hyperpigmentation results from decreased production of melanin.
Signup and view all the answers
What condition describes excessive shedding of hair?
Signup and view all the answers
Study Notes
Factors Causing Skin Injury
- External factors (Exogenous) can lead to skin injuries.
- Internal factors (Endogenous) also contribute to skin damage.
Skin Lesions Classification
- Primary lesions originate from the same organ, directly arising from the underlying disease, and are crucial for diagnosis.
- Secondary lesions evolve from primary lesions and arise through mechanisms such as self-trauma or altered keratinization, less significant for diagnosis.
Primary Skin Lesions
- Macule: Discolored area, ≤ 1 cm; can indicate conditions like lentigo, characterized by hyperpigmentation due to increased melanocytes.
- Papule: Small, round solid elevation of the skin, up to 1 cm.
- Plaque: Larger, flat-topped solid elevation of the skin.
- Nodule: Hard elevation of skin, 1 cm, extending into deeper layers.
- Vesicle: Well-defined elevation of the epidermis < 1 cm filled with clear fluid.
- Bulla: Larger vesicle (blister) > 1 cm filled with fluid.
- Tumor: Large neoplastic mass involving skin structures or subcutis.
- Cyst: Epithelial-lined cavity with fluid or solid material.
- Pustule: Small elevation of the epidermis filled with pus.
- Abscess: Circumscribed accumulation of pus within epidermis or follicles.
- Wheal: Smooth, sharply circumscribed elevation due to dermal edema, often seen in allergic reactions.
Lesions Affecting Skin Surface
- Scale: Accumulation of flakes or dandruff on the skin surface.
- Crust: Dried exudate accumulation alongside blood or serum.
- Comedo: Dilated hair follicle with cornified cells and sebaceous material; common in conditions like hyperadrenocorticism.
Hair Abnormalities
- Alopecia: Hair loss.
- Hypotrichosis: Reduced hair density.
- Atrichia: Failure to develop hair.
- Effluvium/defluxion: Excessive hair shedding.
- Hypertrichosis (hirsutism): Excessive hair growth, can be linked to conditions such as pituitary adenoma in horses.
Alterations in Epidermal Pigmentation
- Hyperpigmentation: Increased melanin production from existing melanocytes.
- Hypopigmentation: Congenital conditions or due to lack of melanocytes or melanin production.
- Pigmentation Incontinence: Loss of melanin from basal epidermal layer.
Factors Influencing Melanin Production
- Influenced by melanocyte-stimulating hormone, age, inflammation, temperature, and genetic factors.
Secondary Skin Lesions
- Epidermal collarette: Circular keratin flakes due to the rupture of a vesicle or pustule.
- Ulcer: Break in epidermis exposing the underlying dermis.
- Excoriation: Erosions or ulcers from scratching or biting.
- Scar: Fibrous tissue replacement in damaged dermis or subcutis.
- Fissure: Linear cleavage in thickened skin.
- Lichenification: Thickening and hardening of skin with exaggerated markings, often seen in conditions like sarcoptic mange.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the portal of entry into the skin, the factors causing injury, and the gross morphology of skin lesions. Focus on primary and secondary lesions, their characteristics, and significance in diagnosis. Test your knowledge on these essential dermatological concepts.
